The major indexes all suffered their biggest weekly declines of the year. The Dow fell 1.6%, the S&P 500 sank 2% and the Nasdaq declined 2.3% over the last five trading days.

Investors have been rattled by concerns about government debt in the euro area and signs that global economic activity is slowing down, according to Simon Hayes, an economist at Barclays Capital. The market will probably continue to focus on these issues next week, which means trading could be volatile.

"A speedy resolution of these issues seems unlikely, and although we expect global activity to improve during the course of the year, the path of financial markets is unlikely to be smooth," Hayes wrote in a research report.

In Europe, investor will be watching auctions of Spanish government bills on Tuesday and bonds on Thursday. Spain has been struggling with rising borrowing costs as investors fear the government will not meet its fiscal targets and may need to be bailed out.

European Central Bank president Mario Draghi will speak at a conference in Frankfurt on Tuesday, and investors will be listening closely for hints that the central bank is prepared to renew its interventions in the bond market.

"Next week sees plenty of data releases from Europe; markets are likely to watch the Spanish bond auction results with particular interest," said Geoffery Kendrick, a foreign exchange strategist at Nomura Securities, in a note to clients. "U.S. economic and earnings data are also frequent, which should help to provide greater clarity in relation to the recent weaker employment data."

Earlier this month, the Labor Department said hiring in March slowed sharply from the month before, although the general trend in payrolls had been improving before that. The jobs report highlighted worries that the recent string of upbeat data was distorted by warm weather, and raised concerns about the outlook for economic growth.

So far, corporate profits and sales have been surprisingly resilient. Of the 32 companies in the S&P 500 that have reported results, 75% have beat earnings expectations and 84% have surpassed sales forecasts, according to FactSet.